Yaeger dons the suit of the dead Mercuy Man from the elevator and outlines the plan for Borman - while he reverses the main engine, Borman needs to reverse the polarity on the three conduits that connect it to the building. The plan in place, the two get to work, with Yaeger threading a gauntlet of invaders to approach the engine. As he gets to work, Borman flips the polarity on the first conduit. The second conduit is flipped, and all seems to be going according to plan. As Borman approaches the third conduit, however, he encounters a lone woman, whose scream attracts the attention of the glowing sentries. She introduces herself as Grace, and Borman attempts to help her escape observation. But the delay leads to problems, as an alarm on the engine begins to sound, alerting the real Mercury Men to Yaeger's work. A battle ensues, with Yaeger emerging victorious. He now has a chance to work on the engine...but is suddenly alerted to the approach of the new sentries. (thetvdb.com)